The proposed research is intended to address the problem of extravasation events in the neonatal and pediatric patient population. Extravasations of intravenous fluids in children can have serious consequences when gross extravasations occur. Skin necrosis can occur which may require treatment with skin grafting. These adverse sequelae are less frequent in the adult patient, but in newborns and young children they are much more prevalent and can be catastrophic. The proposed research is intended to evaluate newly available Passive Microwave Radiometry (PMR) technology as a modality for early detection of extravasation events in children. The PMR technique is passive, non- invasive and measures subcutaneous tissue temperatures. Emphasis will be placed on developing a small, lightweight PMR Sensor consisting of a transducer (antenna) element and a Microwave Monolithic Integrated Circuit (MMIC) radiometric receiver. This Sensor will be integrated into a pre-production pediatric and neonatal extravasation detection system. In-vivo experiments, using an appropriate animal model, will be used to evaluate the ability of the system to distinguish between normal IV infusions and extravasated infusions. The in-vivo performance data collected in the proposed program will be used to develop an extravasation detection algorithm and implemented in an embedded microcontroller based monitor. PROPOSED COMMERCIAL APPLICATION: There is a high incidence of extravasations occurring during the administration of IV fluids in children. One study indicates an 11 percent extravasation rate. The proposed PMR technique is passive, noninvasive and has the potential of being adapted in a small, low cost package for the neonatal and pediatric market. These characteristics will ultimately make conventional IV infusion procedures for the children safer.